It is known that an acrylic block copolymer having methyl methacrylate as a hard segment and butyl acrylate as a soft segment has properties as a thermoplastic elastomer. For example, the mechanical properties of an acrylic block copolymer having a methacryl block and an acryl block which is produced by an iniferter method are disclosed (Patent Reference 1).
The acrylic block copolymer has characteristics excellent in weather resistance, heat resistance, durability, oil resistance and abrasion resistance. Further, an elastomer which is extremely soft in comparison with other thermoplastic elastomers such as a styrene block copolymer can be provided by suitably selecting components composing the block copolymer.
As uses making use of the properties of the acrylic block copolymer, there has been expected development as various superficial skin materials, interior materials, and a material for a part which is directly touched by a hand making use of smooth feeling thereof.
As physical properties necessary for these superficial skin materials, there are resistance to chemicals which may be possibly contacted, further, the adhesivity of superficial skin with a substrate when the superficial skin and the substrate are directly adhered, the adhesivity of the superficial skin with a buffer material when the buffer material is provided between the superficial skin and the substrate, in addition to mechanical properties, scratch resistance, heat resistance, strain restorability. As the molding method of the superficial skin materials, the powder slush molding using soft powder material which is a powder molding method is widely adopted for the superficial skin of interior equipments for an automobile such as an instrument panel, a console box and a door trim. This is caused by that they have soft texture, skin crepe and stitch can be provided, further, the degree of freedom in design is large, and designing property is satisfactory. Since a forming pressure is not applied in the molding method, differing from other molding methods such as injection molding and compression molding, it is a condition that powder flowability is excellent because the powder material is required to be uniformly adhered on a mold with a complicated shape at molding and simultaneously, it is also a condition that melt viscosity is low because powder adhering on a mold is melted and a film is required to be formed by flowing under no pressure. As the material, a polyvinyl chloride sheet has been conventionally widely used because it is excellent in hardness of a surface in use and flexibility, but since a polyvinyl chloride resin contains a lot of chlorine in its molecules, there is fear of great adverse effect on environments and an effective substitute material is desired (Patent Reference 2). Accordingly, a sheet molded article of a thermoplastic elastomer has been conventionally developed as the substitution of the polyvinyl chloride resin (Patent Reference 3, Patent Reference 4, and Patent Reference 5). However, sheets using a polyolefin resin and a styrene elastomer are insufficient in abrasion resistance, flexibility and oil resistance. Further, a sheet using thermoplastic polyurethane was poor in moldability, and also has a problem from the viewpoint of the cost thereof.    Patent Reference 1: Japanese Patent No. 2553134    Patent Reference 2: JP-A-5-279485    Patent Reference 3: JP-A-7-82433    Patent Reference 4: JP-A-10-30036    Patent Reference 5: JP-A-2000-103957